Scales of Justice
When most think of scales, they likely summon an image of Lady Justice, perhaps guarding the entrance of a courthouse, with golden scales for balancing the deeds of the good, the evil and the neutrally aligned. While most weighing is now done by electronically measuring the amount of downward force applied to a plate, a variety of tools have traditionally been used to do this work, Lady Justice’s tool of choice included. This post looks at a selection of scales and weights from two new donations to the Bowers Museum, looking at a unique variant of beam balance scale, one which is still used in Southeast Asia up to the modern day.
How it Works
The scales that we are examining in today’s post go by many different names including dotchin—an Anglicization of the Chinese name—and gănchèng—which directly translates to “stick weight” in Mandarin—but are most often called steelyard scales. Unlike the more traditional balance which has arms of equal length which balance perfectly when nothing is being weighed, this balance is asymetrical. It has a horizontal beam with a cord from which the scale would be held near to a lead-tipped end. This cord denotes the scale's fulcrum. A second fiber cord closer to the end of the same side of the scale has a hook from which either a plate would have held the object that was being weighed, or the item itself could have been directly attached. The other end of the scale has tick marks which tell the user the weight of what is being measured. A bronze weight attached to a third cord could be slid up or down the length of the beam until it and the object in the plate balanced perfectly. Steelyard scales typically are no longer than fourteen inches, which allows the scale to not only be easily accessible, but also portable compared to beam balances.
Roman It’s Way Across Eurasia
There is some evidence that steelyard scales date to at least 5000 years ago, but it is commonly accepted that the modern form developed in Rome, where they were called statera, and China independent from one another around 200 BCE. Since their invention, the scales have seen use throughout the centuries and continued to evolve in their design until relatively recently in the west. Contrary to what the name steelyard scale suggests, these scales were predominantly used in markets to measure metals, foodstuffs and raw materials. Despite weighing a multitude of commodities, the scales also earned their oft-used moniker of “opium scales” by their pervasive use in measuring opium during colonial involvement in the region.
Opium production for medicinal and recreational purposes rose to an all-time high when the British East India Company monopolized the opium trade between the late 18th and the 19th Centuries. Great Britain obtained their opium from India and smuggled it into or sold it in markets across Asia, Europe and the United States. Charters from the East India Company recorded sales comparisons, with one thousand chests of opium sold in 1767 and up to ten times that amount sold per year in the 1820s. While the scales featured in this post would not have taken a central role in the wholesale trade of opium, smaller amounts were often measured using both the steelyard and the standard balance beam scale, earning both the Lao scales and weights the opium prefix. Although the importance and popularity of opium in the West declined in the early 20th Century, it is still often associated with these scales.
A Balancing Act
The larger of the two donations contains nine Laotian scales and nine Laotian weights and the other donation contains one scale from China. Whereas the Laotian scales are made using a thick section of wood covered in lead and bronze, the example from China is much more delicate and uses an ivory beam. The latter would likely have been used to measure more precise amounts than the Laotian example. Also interesting is that despite coming from the same region of the world, the Laotion weights featured in this post would not have been used with this type of scale, but instead with equal arm balances. They were generally not heavy enough to meet the requirements of the sliding weight and would have been difficult to attach to a fiber cord. In general the different types of scales were employed at different times depending on the weight of the object being measured.
Post researched and guest co-written by Victoria McCormack, Volunteer for the Bowers Museum Collections Department. Text and images may be under copyright. Please contact Collection Department for permission to use. References are available on request. Information subject to change upon further research.